To begin learning how to start an online marketplace, first, we need to define what a marketplace is. Digital marketplaces are platforms that connect buyers and sellers of goods or services with each other and provide the infrastructure for the transaction. This can be a platform to sell physical goods like Etsy for homemade gifts or GOAT for rare shoes, or one to find and book services like Rover for pet-sitting or StyleSeat for salon bookings. And of course, there are huge category-defining marketplaces like Airbnb for vacation rentals and Uber for ride-sharing.  

There are always at least two sides in a marketplace, one for supplying the product or service and one for acquiring the product or service. There can even be three-sided marketplaces such as DoorDash, which connects consumers, restaurants, and delivery drivers. Determining who is on each side of your marketplace will be critical as you begin planning your build.
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